Process for preparing detergent compositions



J. B. MARTIN Nov. 22, 1960 PROCESS FOR PREPARING DETERGENT COMPOSITIONSFiled April 2, 1957 ies Hydration of STP II in Aqueous Slurrlmlnpractically no STF-6H O D. IOmln. no STP-GH O E. 25 min. much STP-SH 57in. 2min. much sTP-e H2O 45min. much STP-GH F, 45 mln. much STP-GH O[area/0r Jam .fi'ruae Mari r 2,961,409 Ice Patented Nov. 22, 1960PROCESS FOR PREPARING DETERGENT COMPOSITIONS John Bruce Martin, Wyoming,Ohio, assignor to The Procter & Gamble Company, Cincinnati, Ohio, acorporation of Ohio Filed Apr. 2, 1957, Ser. No. 650,117

7 Claims. (Cl. 252-109) This invention relates to a method for producingheat dried detergent compositions which contain sodium tripolyphosphate.More particularly, this invention relates to a process for producingheat dried detergent compositions which comprises incorporatinganhydrous sodium tripolyphosphate in an aqueous detergent mixture andthen heat drying the resultant slurry.

This application is a continuation-in-part of my copending applicationSerial No. 437,179, filed June 16, 1954, and now abandoned.

Heat dried sodium tripolyphosphate-containing detergent compositions arewell known. Such compositions are commonly produced in the industry byfirst preparing a fluid detergent mixture, adding to this fluid mixturesodium tripolyphosphate and then heat drying the resultant slurry eitherby spray drying or by drying on a heated steel roll.

The sodium tripolyphosphate which is normally used in the production ofsuch detergent compositions is known to exist in two forms-Form I,produced if the phosphate is calcined at high temperature, and Form IIif the phosphate during its manufacture is calcined at lowertemperature. Both of these forms of tripolyphosphate have beenrecognized from time to time as giving rise to certain undesirablecharacteristics in detergent compositions of which they comprise asubstantial part. Thus, Form I sodium tripolyphosphate, in itscommercially available form, when added to a fluid detergent mixturetends to hydrate very rapidly and form hard small lumps or agglomerateswhich persist through the entire processing and appear as hard sand-likeparticles in the final heat dried product. Form II sodiumtripolyphosphate, on the other hand, hydrates rather slowly when addedto a fluid detergent mixture and, unless the crutcher mix is aged as setforth in Hizers US. Patent 2,622,068, has the objectionable tendency ofproducing final heat dried compositions which are sticky in nature andwhich lump and cake badly under even very slight pressure.

In a conventional method for producing heat drietripolyphosphate-containing detergent compositions a fluid detergentmixture, as hereinafter defined, and commonly referred to in theindustry as a crutcher mix, is first prepared. The sodiumtripolyphosphate is then added to this aqueous detergent crutcher mixwith thorough agitation and the resultant slurry is spray dried. It isin connection with this tripolyphosphate-containing crutcher mix thatadditional difliculties are experienced in that after the addition ofthe sodium tripolyphosphate the resultant slurry is rather viscous innature and may be referred to as having a high consistency. This highconsistency usually gives rise to difficulties in mixing, pumping andspraying. If an effort is made to lower the consistency, as by theaddition of more water to the slurry, the amount of moisture which mustbe removed during the spray drying process is increased and thisincreased evaporative load will be reflected in costly decreasedproduction with a given amount of heat input to the spray drying tower.

Moreover, depending upon the particular mixture of anhydroustripolyphosphates being used, variable amounts of hydration tothehexahydrate occurs in the crutcher mix and this tends to causevariations in consistency, in the sprayed particle sizes, and influctuating conditions generally in the spray drying tower as regardstemperature, evaporative load etc., thus causing undesirable nonuniformoperation of the process and non-uniformity in the physicalcharacteristics of the spray-dried product.

It is an object of this invention to provide a method for themanufacture of detergent compositions wherein the rate of hydration ofForm II sodium tripolyphosphate in aqueous fluid detergent mixtures ismarkedly reduced.

This slower hydration rate of the Form II tripolyphosphate promotes theformation of larger sodium tripolyphosphate hexahydrate crystals, asdescribed more completely hereinafter, and the resultant slurryconsequently has a lower and more uniform consistency.

A further object of this invention is to utilize processing advantagesstemming from the lower and more uni-j form consistency of thephosphate-containing crutcher mixes prepared with this more slowlyhydrating Form II sodium tripolyphosphate. I

I have found that these objects may be achieved by taking steps to makesure that Form II sodium tripolyphosphate added to the aqueous detergentcrutcher mix during manufacture of the detergent compositions containsless than 0.1% water, and preferably less than 0.05% water, other thanwater of constitution, as contrasted with the much higher contentsnormally found in supposedly anhydrous tripolyphosphates of commerce.

Wherever herein moisture content values are given for specific samplesof tripolyphosphate, the moisture was determined by the loss on ignitionmethod. Although this method of determining moisture would include anywater of constitution in the phosphate, i.e. water that is chemicallycombined, such as in the sodium hydrogen phosphates, it is to beunderstood that the water of constitution has a negligible effect on theconsistency of phosphatecontaining crutcher mixes.

In the accompanying illustrations: Figures 1A through" 1C arephotomierographs of the hexahydrate crystal structure derived fromslightly hydrous Form II sodium tripolyphosphate after hydration andcrystallization had been allowed to proceed for varying lengths of time;and

Figures 1D through 1F are photomicrographs of the.

hexahydrate crystal structure derived from substantially completelyanhydrous Form II sodium tripolyphosphate after hydration andcrystallization had been allowed to proceed for varying lengths of time.

It is to be understood that the sodium tripolyphosphate referred toherein and in the claims is the normal salt,

oil, babassu oil, soybean oil, castor oil, tallow, whale.

and fish oils, grease and lard, and mixtures thereof) .or ofsynthetically produced fatty acids (e.g. by the oxidation of petroleum,or by hydrogenation of carbon monoxide by the Fischer-Tropsch process),of resin acid (e.g. rosin and those resin acids in tall oil) and/or ofnaphthenic acids. Sodium and potassium soaps can be made by directsaponification of the fats and oils or by? the neutralization of thefree fatty acids which are pre paredin a separate manufacturing process.

(2) Synthetic organic detergents characterized by their high solubilityin water, their resistance to precipitation by the constituents of hardwater and their surface active and effective detergent properties,including:

(a) Anionic synthetic detergents (excluding true soaps): This class ofsynthetic detergentsca'n be broadly described as' thewater-solublesalts, particularly the 'alkali'metal salts, of organic sulfuricreaction products having in the molecular structure an alkyl radicalcontaining from-about 8toabo1it 22 carbon atoms and a'radical selectedfrom the group consisting of sulfonic acid and sulfuric acid esterradicals. Important examples of the synthetic detergents which form apart of the preferred compositions of the present invention are thesodium or potassiumalkyl sulfates, especially those obtained bysulfating the higher alcohols produced by reducing theglycerides oftallow or coconut oil; sodium or potassium alkyl benzene sulfonates, inwhich the alkyl group contains from about 9 to about 15 carbon atoms,especially those of the types described in United States Letters PatentNumbers 2,220,099 and 2,477,383; sodium alkyl glyceryl ether sulfonates,especially those'ethers of the higher alcohols derived from tallowandcoconut oil; sodium coconut oil fatty acid monoglyceride sulfates andsulfonates; sodium or potassium salts of sulfuric acid esters'of thereaction product of one mole of a higher fatty alcohol (e .g. tallow orcoconut oil alcohols) and about three moles of ethylene oxide; sodium orpotassium salts of alkyl phenol ethylene oxide ether sulfate with fourunits of ethylene oxide per'molecule and in which the alkyl radicalscontain about 9carbon atoms; the reaction product of fatty acidsesterified with isethionic acid and neutralized with sodium hydroxidewhere, for example, the fatty acids are derived from coconut oil; sodiumor potassium metal salts of fatty acid amide of a methyl taurine inwhich the fatty acids, for example, are derived from coconut oil; andothers known in the art, a number being specifically set forth in UnitedStates Letters Patent Numbers 2,486,921, 2,486,922 and 2,396,278.

(b) Nonionic synthetic detergents: This class of,syn-

thetic detergents may be broadly defined as compounds produced by thecondensation of alkylene oxide groups (hydrophilic in nature) with anorganic hydrophobic compound, which may be aliphatic or alkyl aromaticin natpre. The length of the hydrophilic or polyoxyalkylene radicalwhich is condensed with any particular hydrophobic group can be readilyadjusted to yield a watersoluble compound having the desired degree ofbalance between hydrophilic and hydrophobic elements,

For example, a well known class of nonionic synthetic detergents is madeavailable on the market under the trade name of Pluronic. Thesecompounds are formed by condensing ethylene oxide with a hydrophobicbase formed by the condensation of propylene oxide with propyleneglycol. The hydrophobic portion of the molecule which, of course,exhibits water insolubility has a molecular weight o f-from about1500.to 1800. The addition of polyoxyethylene radicals to thishydrophobic portion tends to increase the water solubility of themolecule as a whole and the liquid character of the products is retainedup to the point where polyoxyethylene content is about 50% of the totalweight of the condensation product.

"Other suitable nonionic synthetic detergents include: (i) Thepolyethylene oxide condensates of alkyl phenols, e.g. the condensationproducts of alkyl phenols having an alkyl group containing from about 6to 12.

carbon atoms in either a straight chain or branched chain configuration,with ethylene oxide, the said ethylene oxide being present in amountsequal to 10 to 25 moles of ethylene oxide per mole of alkyl phenol. Thealkyl substituent in such compounds may be derived from polymerizedpropylene, diisobutylene, octane, or nonane, for example.

(ii) Those derived from the condensation of ethylene oxide with theproduct resulting from the reaction of propylene oxide and ethylenediamine-products which may be varied in composition depending upon thebalance between hydrophobic and hydrophilic elements which is desired.For example, compounds containing from about 40% to aboutpolyoxyethylene by weight and having a molecular weight of from about5000 to about 11,000, resulting from the reaction of ethylene oxidegroups with a hydrophobic base constituted of the reaction product ofethylene diamine and excess propylene oxide, said base having amolecular weight of the order of2500 to 3000, are satisfactory.

(iii) The condensation product of aliphatic alcohols having from 8 to 18carbon atoms, in either straight chain or branched chain configuration,with ethylene oxide, e.g. a coconut alcohol ethylene oxide condensatehaving from 10 to 30 moles of ethylene oxide per mole of coconut alchol,the coconut alcohol fraction having from 10 to 14 carbon. atoms.

It is to be understood. that the term detergent mixture and/or detergentmix asused herein includes, in addition to one or more of the abovedetergents, alkaline build ers or detergent improving agents such as thesodium and other alkaline carbonates, silicates, phosphates and boratesand/or such compounds as the perborates, persulfates and percarbonates;also organic builders and perfumes, coloring matter, preservatives andother substances commonly found in detergent compositions.

Commercially availableform I and Form II sodium tripolyphosphates, ormixtures thereof, as a rule average above 0.2% in moisture content asreceived, and furthermore tend to be variable in moisture from outsideto inside the mass. It is to be understood of course that this moisturecontent is not inherent in the sodium tripoly phosphate as manufacturedand that as obtained from the calcining kiln thetripolyhosphate iscompletely anhydrous. The moisture content is picked up, usually from.the atmosphere, during subsequent handling of the anhydrous product. Itis to be appreciated that, depending upon the manner by which themoisture in the tripolyphosphate product is picked up, the sodiumtripolyphosphates available on the market vary widely as to the amountof moisture which they contain and moisture contents as high as, 1% orgreater are not unusual.

Itflis the presence of this water in excess of 0.1% which imparts to thesodium tripolyphosphate hydration properties which give rise totheaforementioned undesirable characteristics in detergent compositionspreparedwith them. I have made the totally unexpected discovery that ifthis water is removed, or if its pickup by the triployphosphate isprevented, the hydration characteristics of the tripolyphosphate areradically changed.

The difference in hydration characteristics between a slightly, hydroussample ofForm II sodium tripolyphosphate (about 0.15% water) and asubstantially completely anhydrous Form II sample (0.02% water) isevident from a'comparison of Figures 1A to 1C, photomicrographs, atvarious time intervals, of the slightly hydrous F ormII sodiumtripolyphosphate hydrating and crystallizing as the ,hexahydrate, andFigures 1D to 1F, photomierographs, at variou s] time intervals, of thesubstantially completely anhydrous Form II sodium tripolyphosphatehydrating and cry'stallizing as the hexahydrate.

The technique used in obtaining these photomicrographs .Was as follows:

A small sample of the dry..sodium tripolyphosphate powder was:placed'betweena microscope slide and cover glass. Theflayerfwasthinfenough so that some of the individual particles could'be seen inthe dry form, but not 'softhin that all of the sample dissolved when adrop oflwafter was allowed to flow under the cover glass by capillaryaction. "Agitation ofthe slurry was carefully avoided. Microscopicexamination was made at a magnification of 8 5 diameters with crossednicols.

As can be seen from Figures 1A to 1?, with the,

slightly hydrous Form II sodium tripolyphosphate, prachexahydratecrystals present had further increased. In contrast, with thesubstantially completely anhydrous -Form II sodium tripolyphosphate, nohexahydrate crystals were in evidence less than 10 minutes after theaddition of the water (Fig. 1D). however, much hexahydrate was inevidence but was in After 25 and 45 minutes,

"the form of a few large spherulites rather than in the form of the verysmall hexahydrate crystals obtained with slightly hydrous Form II sodiumtripolyphosphate.

The consistency of the sodium tripolyphosphate-containing crutcher mixslurry is believed to be dependent upon the size of the tripolyphosphatehexahydrate crystals present in the slurry and the larger the size ofthese crystals the lower the consistency of the slurry. Thus, the use ofthe substantially anhydrous tripolyphosphate which results in theformation of larger hexahydrate crystals as hereinbefore described,gives a lower tripolyphosphate-containing crutcher mix consistency andthe mixing, pumping, and spraying advantages which would be inherent insuch a more fluid slurry.

An additional advantage is realized from the use of substantiallycompletely anhydrous Form II sodium tripolyphosphate in accordance withmy invention. The sodium tripolyphosphates have a tendency to undergo ahydrolysis or an intramolecular absorption of water from the hexahydratewith resultant formation of somewhat less alkaline salts of pyroand/ orortho-phosphoric acid, commonly referred to as reversion. This reversionin general occurs only when the tripolyphosphates are in water solutionor slurries at high temperatures and/or during dehydration of theirhydrates, the latter occurring quite commonly during the heat dryingprocess. Since,

-with the use of substantially completely anhydrous Form II sodiumtripolyphosphate less hydration of the tripolyphosphate takes place inthe crutcher mix, the potential for reversion of the tripolyphosphate(during drying) to the less desirable phosphates is reduced.

As has been pointed out in my co-pending application,

{Serial No. 650,190, filed currently herewith, the amount of Form Itripolyphosphate present in the mixture of Form I and Form II of sodiumtripolyphosphates added to the crutcher mix has a profound effect uponcharacteristics of the crutcher mix. Thus, as little as 5% Form I isdetectable in the crutcher mix by the behavior characteristics of thetripolyphosphate, while at Form I, the ascendency of the Form I behaviorcharacteristics is quite evident, and at about 25% or more Form I thebehavior characteristics associated with Form I tripolyphosphatedominate.

Consequently, in order to realize fully the advantages particular to theuse of substantially completely anhydrous Form II tripolyphosphate inaccordance with the present invention, and not identified with the useof substantially completely anhydrous Form I sodium tripolyphosphate, Idesire to include within the scope of my invention only those mixturesof sodium tripolyphosphates containing from about 90 to 100% Form IItripolyphosphate, and, more preferably, sodium tripolyphosphate mixturescontaining greater than about 95% Form II tripolyphosphate.

It is to be noted that the percentage of Form I and Form IItripolyphosphate wherever they appear herein or in the claims areexpressed on the basis of the sodium tripolyphosphates present in themixture of phosphates employed, commercial sodium tripolyphosphatescontaining small percentages of other phosphates, such as orthoorpyro-phosphate, which are incident to the sodium tripolyphosphatemanufacturing process.

' In the following example all consistency measurements '6 given areexpressed in arbitrary units as determined with a commercially availableinstrument called the Brabender Plastograph which records continuouslythe torsion moment required to rotate a pair of agitators in the viscousmixture being examined.

It is to be appreciated in connection with the example, and with thedescribed detergent manufacturing process in general, that when thesodium tripolyphosphate is added rapidly to an aqueous detergentcrutcher mix there is a rapid and large increase in the consistency ofthe mix because of the then poor distribution of the phosphate in themix. The high consistency incident to the tripolyphosphate addition isonly temporary however and the consistency drops oif as thetripolyphosphate is evenly distributed throughout the crutcher mix.Furthermore, it is common practice when making atripolyphosphate-containing detergent to add sodium silicate to thecrutcher mix for several beneficial purposes including inhibition ofaluminum corrosion by the finished detergent product. This silicate isnormally added, because of pH considerations and for convenience,shortly after the tripolyphosphate has been added to the detergentcrutcher mix and the addition therefore frequently occurs when theconsistency of the crutcher mix slurry is at a maximum level as a resultof the tripolyphosphate addition. For these reasons I have chosen to usethe silicate addition as a time base and in the following example theconsistency for any given crutcher mix slurry is expressed for minutesafter the addition of the silicate.

It is to be understood, however, that the above described mode ofexpression is merely for convenience in presenting the examples and thatsome other time basis could just as well have been chosen, the additionof silicate with the process of my invention being optional.

The following specific example is to be considered as illustrative onlyand changes and modifications therein as would normally occur to thoseskilled in the art are contemplated.

Example 1.Two samples of Form II sodium tripolyphosphate, Sample Acontaining 0.15% water, and Sample B containing 0.00% moisture (preparedby igniting a portion of Sample A at 400 C. for two hours), were used toprepare crutcher mix slurries with an aqueous detergent mixturecontaining 9.1% sodium alkyl benzene sulfonate detergent (the alkylradical averaging about 12 carbon atoms and being derived frompolypropylene), 15.1% sodium alkyl sulfate detergent (the alkyl groupsbeing derived from higher alcohols produced by the reduction of tallowand being about 65% C 33% C and 2% C 59.1% water and 15.5% sodiumsulfate, the remainder of the mixture comprising unsulfated material.The tripolyphosphate samples were added in the amount of 371 parts, byweight, to 535 parts, by weight, of the detergent mix. V

93 parts of sodium silicate was added to each of the above mixtures andthe consistency of the resulting slurries was determined with theBrabender Plastograph with the following results. The percent hydrationof the UL polyphosphate in the sample is also given.

7 Percent Hydration Consistency of Slurry Minutes After SilieateAddition HA7) BU AH B STP =sodium tripolyphosphate.

It may be seen from the above data that the anhydrous Form II sodiumtripolyphosphate hydrates at a much slower rate than the slightlyhydrous Form 11 sodium'tripolyphosphate; Also, the ability of theanhydrous Form IIEsodium tripolyphosphate to form and maintain crutchermix slurries of thin consistency is evident.

In the preceding example detergents of each of the various typesenumerated hereinbefore can be substituted for the detergentsspecifically mentioned in the example with comparable results, it beingunderstood that the operation can be readily adjusted to accommodate anyminor changes in crutcher mix consistency resulting from the use ofdifferent detergents. Also, it is to be appreciated thattripolyphosphates of potassium and other alkali metals may be used inconjunction with the sodium tripolyphosphates specifically mentioned,and that the sodium tripolyphosphate-containing detergent compositionsproduced in accordance with my process may be in flake, thread, powderto spray dried granular or powdery form.

Following are some additional examples of the practice of my inventionin which parts shown are by weight.

Example 2.50 parts of completely anhydrous 100% Form II sodiumtripolyphosphate is added to 50 parts of an aqueous detergent mixcontaining about 40% sodium alkyl sulfate detergent (the alkyl groupsbeing derived from the higher alcohols obtained by the reduction ofcoconut oil), 50% water and 10% sodium sulfate. The resultant mixture,after spray drying, is an excellent a1lpurpose detergent.

If desired, the alkyl sulfate detergents in the foregoing example arereplaceable by like amounts of other detergent agents with comparableresults. Thus, sodium alkyl glyceryl ether sulfonate (the alkyl groupsof which are derived from a middle cut coconut fatty alcohol mixturehaving the composition: 10 carbon atoms2%; 12 carbon atoms-66%; 14carbon atoms-23%; and 16 carbon atoms-9%), the sodium salt of sulfatedmonoglyceride of hydrogenated coconut oil fatty acids, the sodium saltof the sulfuric acid esters of the reaction product of one mole of thehigher fatty alcohols derived from the reduction of coconut oil andthree moles of ethylene oxide, the reaction product of coconut oil fattyacids esterified with isethionic acid and neutralized with sodiumhydroxide and the sodium salt of oleic acid amide of N-methyl taurine,all find ready application in the foregoing formulation and provideexcellent general-purpose detergents.

Example 3.40 parts of completely anhydrous Form II sodiumtripolyphosphate is added to 60 parts of an aqueous detergent mixcontaining as a detergent about 25% Pluronic F 68 (the condensationproduct of ethylene oxide with a polyoxypropylene base, the saidpolyoxypropylene base having a molecular weight of about 1500 to about1800, and the said condensation product having a molecular weight ofabout 8000), 15% sodium sulfate, sodium silicate and 55% water. Theresultant mixture, after spray drying is an excellent detergent agent,particularly in uses where excessive sudsing is not desirable.

Other nonionic synthetic detergents, such as, Igepal CO-720 (a nonylphenol ethylene oxide condensate having on the average 15 moles ofethylene oxide per mole of nonyl phenoyl), the alkyl ethylene oxidecondensate wherein the alkyl radical is derived from alcohols producedby the reduction of coconut oil fatty acids having from 10 to 14 carbonatoms, the said condensate having an average molecular weight of about800, and Tetronic 707 (a commercially available nonionic condensationproduct identified by a molecular weight of about 11,000 and obtainedfrom the condensation of ethylene oxide with a hydrophobic base derivedfrom the condensation of propylene oxide with ethylene diamine, saidbase having a molecular weight of the order of 2500 to 3000), arereadily substituted for the Pluronic P68 in the foregoing example inlike amounts with comparable results.

Example 4.-33 parts of completely anhydrous Form II sodiumtripolyphosphate is added to 67 parts of an aqueous detergent mixturecontaining about 15% sodium alkyl benzene sulfonate detergent (the alkylradical averaging about 12 carbon atoms and being derived frompolypropylene), about 37% of a sodium soap. obtained by thesaponification of tallow, about 5% sodium sulfate and about 43% water.The resultant mixture is spray dried and gives an excellent detergentagent having a relatively low sudsing level.

The substitution, in like amounts, of a sodium soap obtained by thesaponificatiou of coconut oil for the sodium soap obtained by thesaponification of tallow in the above example results in a detergentcomposition having comparable performance characteristics. Also, withany of the foregoing compositions drying is readily accomplished on aheated steel roll with comparable results.

Example 5.-25 parts of completely anhydrous Form 11 sodiumtripolyphosphate is added to parts of an aqueous solution of 50% soap(normal sodium kettle soap obtained from the saponification of a mixtureof tallow and 20% coconut oil), 45% water and 5% sodium silicate. Themixture, after spray drying, is an excellent detergent having balancedsudsing and cleansing properties.

In the above example, the substitution, in like amounts, of the normalsodium kettle soap obtained from the saponification of a mixture of 60%palm oil, 20% babassu oil and 20% hydrogenated marine oils, for thenormal sodium kettle soap specified gives comparable results. Thesubstitution of normal potassium kettle soap for the sodium kettle soapin any of the foregoing compositions of this example is also readilyaccomplished and results in detergent compositions having comparableperformance characteristics.

The utility of the invention is particularly attractive in themanufacture of detergent compositions wherein the ratio of sodiumtripolyphosphate to organic detergent ranges from about 1:1 to 5:1 andthe weight of water used in making the fluid mixture to be spray drieddoes not exceed the weight of tripolyphosphate used.

It is to be pointed out that in the manufacture of detergents inparticulate form which contain substantial amounts of sodiumtripolyphosphates, little of the tripolyphosphate is in solution duringthe processing of the crutcher mix, most of it being suspended as aslurry. Consequently, in order to insure the desired rapid solution ofthe final detergent product in water, the particle size of the sodiumtripolyphosphate should be regulated and should, in general, be nolarger than that desired in the final product.

Having thus described my invention, I claim:

1. In the process of producing a heat dried detergent compositioncontaining substantial amounts of sodium tripol 'phosphate, the step ofincorporating a substantially completely anhydrous sodiumtripolyphosphate containing from about to of Form 11 sod.umtripolyphosphate and containing not more than 0.1% water, other thanwater of constitution, in a fluid detergent mixture, containingessentially (a) an organic detergent selected from the group consistingof sodium and potassium salts of higher molecular weight carboxylicacids, water soluble salts of organic sulfuric reaction products havingin their molecular structure an alkyl radical containing from about 8 toabout 22 carbon atoms and a radical selected from the group consistingof sulfonic acid and sulfuric acid ester radicals, and water solublenonionic synthetic detergent condensation products of alkylene oxidegroups which are hydrophilic in nature with an organic hydrophobiccompound selected from the group consisting of aliphatic compounds andalkyl, aromatic compounds, the ratio of sodium tripolyphosphate toorganic detergent ranging from about 1:1 to 5:1, and (b) more thansufficient water to hydrate the sodium tripolyphosphate added andsufficient to provide and maintain a fluid detergent mixture, wherebythe rate of hydration of the Form 11 sodium tripolyphosphate to thehexahydrate is decreased and the fluid detergent mixture remains fluid.

2. The process of claim 1 wherein the sodium tripolyphosphate containsnot more than 6.05% water, other than water of constitution.

3. The process of claim l wherein the sodium tripolyphosphate addedcontains greater than about 95% Form II sodium tripolyphosphate.

4. The process of claim 1 wherein the sodium tripolyphosphate is whollyanhydrous Form I1 tripolyphosphate.

5. The process of claim 1 wherein the weight of the water used in makingthe fluid mixture does not exceed the weight of said tripolyphosphate.

6. In the process of producing a heat dried detergent compositioncontaining substantial amounts of sodium tripolyphosphate, the stepswhich comprise, (1) drying a commercially available sodiumtripolyphosphate containing from about 90% to 100% Form II sodiumtripolyphosphate to a uniformly substantially completely anhydrouscondition wherein not more than 0.1% water, other than water ofconstitution, is present, and (2) incorporating the thus driedtripolyphosphate in a fluid detergent mixture containing essentially (a)an organic detergent selected from the group consisting of sodium andpotassium salts of higher molecular weight carboxylIc acids, watersoluble salts of organic sulfuric reaction products having in theirmolecular structure an alkyl radical containing from about 8 to about 22carbon atoms and a radical selected from the group consisting ofsulfonic acid and sulfuric acid ester radicals, and water solublenonionic synthetic detergent condensation products of alkylene oxidegroups which are hydrophilic in nature with an organic hydrophobiccompound selected from the group consisting of aliphatic compounds andalkyl aromatic compounds, the ratio of sodium tripolyphosphate toorganic detergent ranging from about 1:1 to :1, and (b) more thansufficient water to hydrate the tripolyphosphate added and sufficient toprovide and maintain a fiuid detergent mixture, whereby the rate ofhydration of the Form II sodium tripolyphosphate to the hexahydrate isdecreased and the fluid detergent mixture remains fluid.

7. In the process of producing a heat-dried detergent compositioncontaining substantial amounts of sodium tripolyphosphate, the stepswhich comprise, (1) maintaining sodium tripolyphosphate containing fromabout to Form 11 sodium tripolyphosphate substantially in its initialcompletely anhydrous state wherein not more than 0.1% water, other thanthe water of constitution, is present, and (2) incorporating the saidtripolyphosphate in a fluid detergent mixture containing essentially (a)an organic detergent selected from the group consisting of sodium andpotassium salts of higher molecular weight carboxyl.c acids, watersoluble salts of organic sulfuric reaction products having in theirmolecular structure an alkyl radical containing from about 8 to about 22carbon atoms and a radical selected from the group consisting ofsulfonic acid and sulfuric acid ester radicals, and water solublenonionic synthetic detergent condensation products of alkylene oxidegroups which are hydrophilic in nature with an organic hydrophobiccompound selected from the group consisting of aliphatic compounds andalkyl aromatic compounds, the ratio of sodium tripolyphosphate toorganic detergent ranging from about 1:1 to 5:1 and (b) more thansufficient water to hydrate the tripolyphosphate added and suflicient toprovide and maintain a fluid detergent mixture, whereby the rate ofhydration of the Form 11 sodium tripolyphosphate to the hexahydrate isdecreased and the fluid detergent mixture remains fluid.

References Cited in the file of this patent UNITED STATES PATENTS2,396,278 Lind Mar. 12, 1946 2,486,922 Strain Nov. 1, 1949 2,622,068Hizer Dec. 16, 1952 2,773,833 Lewis et a1. Dec. 11, 1956 FOREIGN PATENTS680,346 Great Britain Oct. 4, 1952

1. IN THE PROCESS OF PRODUCING A HEAT DRIED DETERGENT COMPOSITIONCONTAINING SUBSTANTIAL AMOUNTS OF SODIUM TRIPOLYPHOSPHATE, THE STEP OFINCORPORATING A SUBSTANTIALLY COMPLETELY ANHYDROUS SODIUMTRIPOLYPHOSPHATE CONTAINING FROM ABOUT 90% TO 100% OF FORM 11 SODIUMTRIPOLYPHOSPHATE AND CONTAINING NOT MORE THAN 0.1% WATER, OTHER THANWATER OF CONSTITUTION, IN A FLUID DETERGENT MIXTURE, CONTAININGESSENTIALLY (A) AN ORGANIC DETERGENT SELECTED FORM THE GROUP CONSISTINGOF SODIUM AND POTASSIUM SALTS OF HIGHER MOLECULAR WEIGHT CARBOXYLICACIDS, WATER SOLUBLE SALTS OF ORGANIC SULFURIC REACTION PRODUCTS HAVINGIN THEIR MOLECULAR STRUCTURE AN ALKYL RADICAL CONTAINING FROM ABOUT 8 TOABOUT 22 CARBON ATOMS AND A RADICAL SELECTED FROM THE GROUP CONSISTINGOF SULFONIC ACID AND SULFURIC ACID ESTER RADICALS, AND WATER SOLUBLENONIONIC SYNTHETIC DETERGENT CONDENSATION PRODUCTS OF ALKYLENE OXIDEGROUPS WHICH ARE HYDROPHILIC IN NATURE WITH AN ORGANIC HYDROPHOBICCOMPOUND SELECTED FROM THE GROUP CONSISTING OF ALIPHATIC COMPOUNDS ANDALKYL AROMATIC COMPOUNDS, THE RATIO OF SODIUM TRIPOLYPHOSPHATE TOORGANIC DETERGENT RANGING FROM ABOUT 1:1 TO 5:1, AND (B) MORE THANSUFFICIENT WATER TO HYDRATE THE SODIUM TRIPOLYPHOSPHATE ADDED ANDSUFFICIENT TO PROVIDE AND MAINTAIN A FLUID DETERGENT MIXTURE, WHEREBYTHE RATE OF HYDRATION OF THE FORM 11 SODIUM TRIPOLYPHOSPHATE TO THEHEXAHYDRATE IS DECREASED AND THE FLUID DETERGENT MIXTURE REMAINS FLUID.